This is an excellent coupler for smaller dogs. I have one rather small dog and another that is medium size. This adjustable leash is perfect for walking them at the same time. Using two separate leashes is sometimes trying, but I have no problems with this. I use a rather long lead which works fine since both of the smaller dogs are well trained. I have used this one two of our larger hounds, and must warn you that you need full control over your animals if they are hooked together. Two large hunting dogs can drag you off your feet if they desire. I am not that large and they know it.
This is a comfortable coupler on the hand and the dogs do not seem to mind it one bit. This price is very good. I paid almost double the price that is quoted here for the same product.